I've owned a lower end pair of Morrow Cables, Rick Straley cables, Anticables, and Cardas cables that retail for twice the price of the Clear Days.
All I can tell you is that in MY SYSTEM, which has tube based amplification and very revealing North Creek Rhythm Revelator speakers, the Clear Day silver cables are very clearly the best set of speaker cables I've ever owned.
As mentioned above, the background is black and dead silent. Micro details, instrument separation, tone and pitch, imaging width and depth, dynamics, and PRaT are all there in spades. With the right associated gear, these cables will make your whole system take a quantum leap forward. At least that has been my experience. My set-up is truly mid-fi: modded Fisher 500c, tube based EE Minimax CDP, the Northcreek speakers mentioned above, and a big honkin' Velodyne ULD-18 subwoofer.
But for the first time I can honestly say I've tasted a bit of the high-end thanks to the Clear Day cables.
And on top of the gear, I can't say enough about Paul Laudati, the man behind the product. He is a truly passionate audiophile as well as one of the most gracious and accommodating fellows you'll ever meet in the audio world. He has personally bent over backwards to help me cable my system, and he will actually talk you out of buying his product if he doesn't think it will synergize well with your gear.
Comparing product quality and service, IMHO Clear Day is the clear winner.